When talking about the useful life of a product or its failure rate, we are not referring to one particular means of quantifying this data. HOLALUX uses the LM-80 method and the TM-21 projection for the measurement of lumen maintenance in LED light sources. These tests were developed by the IES and adopted globally by the lighting industry, such that they give the customer and user the most reliable and standardized data on the market. This data allows us to establish the useful life and quality standards of the product, to determine the guarantee and to develop new products according to characteristics of the light sources.
The LM-80 method consists of measuring the light output of an LED at demanding temperatures for a period of between 6,000 and 10,000 hours. in order to adapt the measurement to the conditions of use during the useful time for users. IES published the TM-21 method, which estimates the light degradation of the LEDs using data obtained with the LM-80 method.
Typical market projections consist in considering that the minimum luminosity value of a luminaire perceived by the user is 70% of the initial value(L70) for 50,000 hours of life, although we the manufacturers can increase those values by striving for better quality standards for our products. For example, the HOLALUX’s ALTALUX series guarantees a minimum of 80% luminosity of the LED for 60,000 hours.
In addition to the above-mentioned lumen maintenance, this data is normally accompanied by the maximum percentage of luminaires that will not correctly correspond to the extrapolation made in the laboratory.
It is also important that this data is accompanied by a specific temperature control value (Tc), as operating temperature is crucial In LED technology.